Technical Field
Embodiments described herein are related to the field of integrated circuits, and more particularly to a battery management circuit to communicate between integrated circuits and provide battery protection.
Description of the Related Art
Computing systems may include one or more systems-on-a-chip (SoCs), which may integrate a number of different functions, such as application execution, graphics processing, and audio processing, onto a single integrated circuit. With numerous functions included in a single integrated circuit, chip count may be kept low in mobile computing systems, such as tablets, for example, which may result in reduced assembly costs, and a smaller form factor for such mobile computing systems.
Various computing systems may include one or more power sources, such as batteries for example, for supplying power to some or all of the system. For various reasons, a current provided by one or more of the power sources (i.e., a supply current) may be monitored within the system. Supply currents may be monitored, for example, to track and compare power consumed by one or more portions of the computing system, to estimate a remaining power available from the power source, or to profile energy usage over time. One method for monitoring a current from a power source includes placing a resistor in series with the power source and measuring a voltage level across the resistor. Using Ohm's law, a value for the current may be determined from the resistance of the resistor and the voltage level across the resistor. This method, however, requires the addition of a resistor that remains in the power supply path even if current measurements are not actively being taken, which may result in power wasted through the resistor and, therefore, not available to the system. This resistor may also be an added component to the system that may not be used for any other purpose than current measurements, thereby adding cost.